diff --git a/Dockerfile b/Dockerfile
index 59d42084..35fef53f 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -33,7 +33,6 @@ RUN pip install --no-cache-dir /deps/*.whl
 
 COPY --from=builder /doccano /doccano
 
-ENV IS_HEROKU="False"
 ENV DEBUG="True"
 ENV SECRET_KEY="change-me-in-production"
 ENV PORT="80"
diff --git a/app/app/settings.py b/app/app/settings.py
index c4e804d4..2bd86126 100644
--- a/app/app/settings.py
+++ b/app/app/settings.py
@@ -195,6 +195,8 @@ LOGIN_URL = '/login/'
 LOGIN_REDIRECT_URL = '/projects/'
 LOGOUT_REDIRECT_URL = '/'
 
+django_heroku.settings(locals(), test_runner=False)
+
 # Change 'default' database configuration with $DATABASE_URL.
 DATABASES['default'].update(dj_database_url.config(
     env='DATABASE_URL',
@@ -202,6 +204,10 @@ DATABASES['default'].update(dj_database_url.config(
     ssl_require='sslmode' not in furl(env('DATABASE_URL', '')).args,
 ))
 
+# work-around for dj-database-url: explicitly disable ssl for sqlite
+if DATABASES['default'].get('ENGINE') == 'django.db.backends.sqlite3':
+    DATABASES['default'].get('OPTIONS', {}).pop('sslmode', None)
+
 # Honor the 'X-Forwarded-Proto' header for request.is_secure()
 SECURE_PROXY_SSL_HEADER = ('HTTP_X_FORWARDED_PROTO', 'https')
 
@@ -218,11 +224,3 @@ AZURE_APPINSIGHTS_IKEY = env('AZURE_APPINSIGHTS_IKEY', None)
 APPLICATION_INSIGHTS = {
     'ikey': AZURE_APPINSIGHTS_IKEY if AZURE_APPINSIGHTS_IKEY else None,
 }
-
-# work-around for django-heroku: don't overwrite sslmode outside of heroku
-if env.bool('IS_HEROKU', True):
-    django_heroku.settings(locals(), test_runner=False)
-
-# work-around for dj-database-url: explicitly disable ssl for sqlite
-if DATABASES['default'].get('ENGINE') == 'django.db.backends.sqlite3':
-    DATABASES['default'].get('OPTIONS', {}).pop('sslmode', None)
diff --git a/app/server/tests/test_config.py b/app/server/tests/test_config.py
index f1bcfd84..7a175d3d 100644
--- a/app/server/tests/test_config.py
+++ b/app/server/tests/test_config.py
@@ -17,8 +17,7 @@ class TestDatabaseUrl(TestCase):
             self._assert_sslmode_is(None)
 
     def test_sslmode_can_be_set_via_database_url(self):
-        with setenv('DATABASE_URL', 'pgsql://u:p@h/d?sslmode=disabled'), \
-             setenv('IS_HEROKU', 'False'):
+        with setenv('DATABASE_URL', 'pgsql://u:p@h/d?sslmode=disabled'):
             self._assert_sslmode_is('disabled')
 
     def _assert_sslmode_is(self, expected):